CVE-2026-121941

{
  "id": "CVE-2026-121941",
  "sourceIdentifier": "[email protected]",
  "published": "2026-11-04T13:17:28.560",
  "lastModified": "2026-11-04T13:17:28.560",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "libmt32emu before 2.8.4 contains a heap buffer overflow vulnerability in MidiStreamParserImpl::parseSysex that allows attackers to write past a heap allocation by supplying oversized unterminated SysEx messages. Attackers can feed more than 32768 SysEx data bytes through the mt32emu_parse_stream API via MIDI files, ports, or sequencer clients to corrupt heap memory and crash the application."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "munt",
          "product": "libmt32emu",
          "defaultStatus": "unaffected",
          "repo": "https://github.com/munt/munt",
          "packageURL": "pkg:github/munt/munt",
          "versions": [
            {
              "version": "0",
              "lessThan": "2.8.4",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 8.5,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "PASSIVE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-122"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/munt/munt/blob/libmt32emu_2_8_3/mt32emu/src/MidiStreamParser.cpp#L223-L257",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/munt/munt/commit/1749f7fed5cdb3a9015acce076a1512b1615dc3b",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/munt/munt/issues/149",
      "source": "[email protected]"
    },
    {
      "url": "https://hackmd.io/@haindpwn/munt-midistreamparser-oversized-sysex-heap-overflow",
      "source": "[email protected]"
    },
    {
      "url": "https://www.vulncheck.com/advisories/libmt32emu-before-2.8.4-heap-buffer-overflow-via-midistreamparserimpl-parsesysex",
      "source": "[email protected]"
    }
  ]
}